Fred, Are you looking for marketing data lists or actual leads where people are looking for the service you offer?

That may be data that feeds into Josh's link to the top 21 books.

You can also check the tax data base for out of area owners who have bought property in the last year.Also check Craigslist for landlords...call and ask if they're interested in more properties at a great discount.Throw out a few bandit signs around the neighborhood....But the BEST way is to know what your buyers want first, then go out and find it.

Once these leads are data-mined, I have our skip tracers look up #s, information is uploaded to our auto-dialer & CRM, then I have my cold caller(s) reach out to all the various categories I target. 

You can check with the state department of natural resources which have public data on all wells drilled and the production on each one.

Being a data-driven guy, I think it's important to identify a few key metrics (or KPIs - key performance indicators) that show how well a property is performing. 

I have been following the Philly market for a while and used an analysis tool that pulls data from Airbnb and VRBO to verify what other hosts are making, with what type of properties, and in what areas.

I could provide data to show this.Thanks for the response!

Everybody says excel seems like it takes forever to enter data in excel!

The best compilation of actual job & leasing data is CBRE's Tech 30 report.